Lock for foundry flasks



Feb. 13, 1968 s. E. WOOD LOCK FOR FOUNDRYFLASKS Filed Oct. 24. 1965 STANLEY E. WOOD BY Ma m gm United States Patent Otlice 3,368,609 Patented Feb. 13, 1968 3,368,609 LOCK FOR FOUNDRY FLASKS Stanley E. Wood, 1104 th Ave., Grafton, Wis. 53024 Filed Oct. 24, 1965, Ser. No. 504,907 5 Claims. (Cl. 164-386) This invention relates to a lock for connecting the cope and drag flasks used in a foundry mold.

In the preferred embodiment herein disclosed, the cope flask r-ail has an aperture through which a taper pin fixed in the drag flask rail projects when the cope and drag are assembled. A plate on the cope flask rail carries guide pins which project upwardly to locate and guide a mounting plate upon which there is a housing of upwardly tapering form which serves to wedge against the taper pin a pair of complementary jaws which are normally spring biased apart.

The wedging action is such that the housing is readily depressed manually to lock the jaws against the taper pin and thereby to lock the cope and drag flasks in assembly. Tongue and groove guides are desirably provided between the jaws and the housing so that the jaws will be properly keyed in operative position to engage the taper pm.

When it is desired to release the cope flask from the drag flask, a light manual upward tension on the housing releases the wedging pressure of the housing against the jaws. The jaws are there-upon opened by their spring bias to free the taper pin. The flasks are then completely free.

As many locks may be provided as are needed for a particular installation. Normally one lock at each end of the flask assembly is sufficient.

In the drawings:

FIG. 1 is a fragmentary view in end elevation of cope and drag flasks equipped with a lock embodying the invention, the lock being shown in open position.

FIG. 2 is a view similar to FIG. 1 but with parts broken away and showing the parts as they appear when the jaws are locked upon the taper pin.

FIG. 3 is a detail view of the lock mechanism in side elevation, portions of the flasks being fragmentarily illustrated.

FIG. 4 is a view taken in transverse section on the line 4-4 of FIG. 2.

In accordance with conventional practice, the drag flask 6 and the cope flask 8 are provided respectively with rails 10 and 12. Mounted on the drag flask rail 10 is a taper pin 14 which constitutes the upper part of a post 16. The post has a shoulder 18 which rests on the drag flask rail 10. An extension bolt 20 is carried through the drag flask rail and secured thereto by a nut 22 and lock washer 24.

Taper pin 14 has a downwardly tapering frusto-conical surface 26 and desirably may be provided above the cylindrical zone 28 with an upwardly tapering frusto-conical surface 30, the latter being optional.

The cope flask rail 12 has a fairly large opening at 32 through which the post 16 of the taper pin 14 projects freely. No attempt is made to provide a tight fit between the post and the cope flask rail. On the cope flask rail is a mounting plate 34 with an opening at 36 which registers with the opening 32 in rail 12. The length of the taper pin 14 is such that its tapered surface 26 lies above the mounting plate 34.

Projecting upwardly from the mounting plate 34 are guide pins 38 for a wedge housing 40 which has a flange 42 slidably bearing on these pins and confined between heads 44 thereof. Resting on the mounting plate 34 and having their upper ends confined within the housing 40 are the locking jaws 50, each of which has frusto-conical inner faces 52, complementary to the tapered surfaces 26 of pin 14 and faces 54 complementary to the surfaces 30 of pin 14. The jaws have pockets at 56 engaged by the ends of springs 58 which normally bias the respective jaws apart to free them from the intervening taper pin 14.

Externally, the jaws have downwardly inclined faces 60 along which extend central ribs at 62. The wedge housing 40 has complementary downwardly inclined camming surfaces at 64 and channels 66 in which the respective ribs are engaged for guidance.

A handle flange 68 is desirably provided on the top of the wedge housing 40.

With the cope flask superimposed on the drag flask and the taper pin 14 projecting through the cope flask rail and the mounting plate 34, as shown in FIG. 1, even a light manual pressure exerted through the handle 68 or otherwise upon the wedge housing 40 will cam the floating jaws 50 into locking engagement with the taper pin 14 as shown in FIGS. 2 and 4. The lock achieved is extremely secure and will remain effective until released by upward displacement of the wedge housing 40. Again, it is readily possible to effect this unlocking operation manually, there being little resistance to upward movement of the wedge housing to permit the springs 58 to effect lateral retraction of the jaws 50 from the engagement with the taper pin.

By way of example and not by way of limitation, it may be noted that in practice it is preferred that the lock housing 40 be made of ductite iron internally machined to provide the bearing surfaces 64 and 66. The jaws are preferably made of grey iron and are likewise machined to provide the bearing surfaces at 60 and 62. Both the guide and taper pins are desirably made of carbon steel.

I claim:

1. A lock for connecting cope and drag flasks used in a foundry and having complementary rails, said lock comprising a taper pin connected with the rail of one flask and projecting through an aperture with which the rail of the opposing flask is provided, a jaw having a lock surface complementary to that of the taper pin and normally spaced therefrom, and a wedge housing having a camming surface engageable with said jaw for camming the jaw into operative engagement with the taper pin, and means mounted on said other flask for positioning the jaw and the wedge housing and for guiding the wedge housing for reciprocation axially of the taper pin.

2. A lock for connecting cope and drag flasks having complementary rails, said lock comprising a taper pin connected with the rail of one flask and extending through an aperture with which the rail of the other flask is provided, a mounting plate on the apertured rail of the other flask, guide pins on the mounting plate, a wedge housing reciprocable toward and from the aperture rail of the other flask and having guide means engaging said pins, a pair of jaws normally spaced at opposite sides of the taper pin and having locking surfaces complementary to the surfaces of the taper pin and adapted when engaged therein to lock the jaws to the taper pin, the jaws being mounted on said plate and within said housing, and the housing and jaws having complementary wedging surfaces whereby the reciprocation of the housing moves the jaws into engagement with the taper pin.

3. A lock according to claim 2 in which spring means act on the jaws to bias them toward positions free of the taper pin.

4. A lock according to claim 2 in which the said bearing surfaces of the wedge housing and the jaws have complementary tongue and groove means for positioning the aws.

5. A lock for connecting foundry cope and drag flasks having rails, said lock comprising a taper pin having a downwardly tapering frusto-conical lock surface and means for mounting the pin on a drag flask rail, the cope flask rail having an aperture through and above which said 3 pin projects, a mounting plate adapted to be mounted on the cope flask rail and having an aperture for said pin, guide pins on said plate, a wedge housing having means bearing on the guide pins, said wedge housing being reciproca-ble along the guide pins toward and from said plate, a pair of jaws disposed at opposite sides of the taper pin and having transversely concave surfaces complementary to the surfaces of the taper pin for locking engagement therewith, spring means biasing said jaws away from said pin, said jaws being normally spaced laterally from the taper pin, the jaws being supported from said plate and having their upper ends engaged in said wedge housing, the jaws and the wedge housing having complementary camming surfaces progressively increasing in cross section in a direction downwardly toward said plate, whereby the reciprocation of the wedge housing toward said plate cams the References Cited UNITED STATES PATENTS 7/1926 White 249219 FOREIGN PATENTS 654,400 12/1962 Canada.

I. SPENCER OVERHOLSER, Primary Examiner.

R. D. BALDWIN, Assistant Examiner. 

1. A LOCK FOR CONNECTING COPE AND DRAG FLASKS USED IN A FOUNDRY AND HAVING COMPLEMENTARY RAILS, SAID LOCK COMPRISING A TAPER PIN CONNECTED WITH THE RAIL OF ONE FLASK AND PROJECTING THROUGH AN APERTURE WITH WHICH THE RAIL OF THE OPPOSING FLASK IS PROVIDED, A JAW HAVING A LOCK SURFACE COMPLEMENTARY TO THAT OF THE TAPER PIN AND NORMALLY SPACED THEREFROM, AND A WEDGE HOUSING HAVING A CAMMING SURFACE ENGAGEABLE WITH SAID JAW FOR CAMMING THE JAW INTO OPERATIVE ENGAGEMENT WITH THE TAPER PIN, AND MEANS MOUNTED ON SAID OTHER FLASK FOR POSITIONING THE JAW AND THE WEDGE HOUSING AND FOR GUIDING THE WEDGE HOUSING FOR RECIPROCATION AXIALLY OF THE TAPER PIN. 